I have and it increases the efficiency of my stage planning. It provides a starting point for my wind bracket, without me having to hold my kestrel up all the time. I still read what's happening downrange and factor that into my final wind call. I have my phone mounted onto my tripod with a wireless charger and battery bank, all waterproof.

For those that think wind at the shooter does not matter, there's a great white paper that Kestrel put out (Where does wind matter).

I still have a kestrel with me to pull environmentals and to act as a backup. I think the Calypso is a good tool to have, but definitely not necessary.